FatfreeGTO

I'm copying this from my build thread in the conversions section, please check out my dyno chart and let me know what you guys think good?? bad?? either way. This is in a 66 GTO mainly used for cruising.

Ok got the car back from the tuner. Just a reminder of what I'm working with
- 2008 6.0L LY6 30k miles, 2009 4l80e 2k miles all stock both from junkyards.
- L92 heads stock
- VVT cam stock
- 1 3/4" primary full length headers, 3" collector, reduces to 2.5" pypes x- pipe dual exhaust
- LS3 intake manifold, rails, injectors.
- LS7 90mm throttle body, 85mm truck MAF
- Diy 4" diameter cold air intake.

First run right off the bat just how I brought it in are shown as the lower of the 2 blue and red lines. Peak #'s were 333.9 HP @ 5410 rpm and 356.5 TQ @ 4575 Rpm. After tuning the final result is shown in as the upper red and blue line 343 HP @ 5293 RPM, and 364.8 TQ @ 4632 RPM. So basically I got 10 HP and 10 TQ peak gain but.... if you look in the midrange some areas show a 40-50 hp gain around 3300 rpm and close to 70 ft lbs of TQ again around 3300 rpm!! In addition to the gains overall driveablility was improved, I notice a much nicer idle, firmer shifts at wide open throttle, better throttle response, and the car is burning rubber like you wouldn't believe (well i'm sure you guys know ) If you correct for driveline loss basically the engine is making at a minimum 405 hp (15% loss) but more realistically 430 hp because the 4l80e robs tons of HP or about a 20% loss. These numbers are honestly 25-30 hp higher then I was expecting so I am more then happy.

Also what this graph is showing is that I need a more aggressive cam for sure because the engine is good to 6500 rpm but I'm dropping off so much up top. With a new cam and another tune I could realistically add 75-100 hp on top of where I'm at now, but then I will need to change the stall converter in the trans as well to take full advantage at that point... It never ends! Again I am so happy with what I currently have, never have I had a car lay 50' plus of rubber shifting into second gear while floored but this one did tonight on the way home

Here is the graph, be sure to read what I write below and advise me on what to do...



So I ask the tuner if they made any adjustments to the stock VVT cams phaser table and he tells me my ECU doesn't have any phaser tables in it... My engine has a VVT cam but speartech didn't send me and ECU with VVT in it like I asked, and I'm kinda pissed about that! I have a corvette ECU. I just paid $450 to have the car tuned $100 of that was registering my ecu with HP tuners. If I get a different ECU to take advantage of VVT I will have to spend the $100 registration again. I have had other cars in the past with different / more advanced versions of this VVT but I believe in it and I really wanted to utilize it here. Both from a performance standpoint, and from a uniqueness standpoint. A cam upgrade is in the future plans there is no doubt about it, and I wanted it to be a VVT cam, and I planned my whole front accessory drive around spacing out for the VVT, so...

- Should I call speartech and ask him WTF, and try to get him to send me an ecu like I asked and paid for?

- Or should I just forget about it, move on, do the VVT delete in the future when I upgrade the cam, and not even tell Speartech that he f'ed up?

Well anyways regardless of all that I'm a happy camper tonight and this swap has been worth all the frustration and cost without a doubt!